Chrome-devtools-mcp memory-leak-debugging

Diagnoses and resolves memory leaks in JavaScript/Node.js applications. Use when a user reports high memory usage, OOM errors, or wants to analyze heapsnapshots or run memory leak detection tools like memlab.

install
source · Clone the upstream repo
git clone https://github.com/ChromeDevTools/chrome-devtools-mcp
Claude Code · Install into ~/.claude/skills/
T=$(mktemp -d) && git clone --depth=1 https://github.com/ChromeDevTools/chrome-devtools-mcp "$T" && mkdir -p ~/.claude/skills && cp -r "$T/skills/memory-leak-debugging" ~/.claude/skills/chromedevtools-chrome-devtools-mcp-memory-leak-debugging && rm -rf "$T"
manifest: skills/memory-leak-debugging/SKILL.md
source content

Memory Leak Debugging

This skill provides expert guidance and workflows for finding, diagnosing, and fixing memory leaks in JavaScript and Node.js applications.

Core Principles

  • Prefer
    memlab
    :
    Do NOT attempt to read raw
    .heapsnapshot
    files directly, as they are extremely large and will consume too many tokens. Always recommend and use
    memlab
    to process snapshots and identify leak traces.
  • Isolate the Leak: Determine if the leak is in the browser (client-side) or Node.js (server-side).
  • Common Culprits: Look for detached DOM nodes, unhandled closures, global variables, event listeners not being removed, and caches growing unbounded. Note: Detached DOM nodes are sometimes intentional caches; always ask the user before nulling them.

Workflows

1. Capturing Snapshots

When investigating a frontend web application memory leak, utilize the

chrome-devtools-mcp
tools to interact with the application and take snapshots.

  • Use tools like
    click
    ,
    navigate_page
    ,
    fill
    , etc., to manipulate the page into the desired state.
  • Revert the page back to the original state after interactions to see if memory is released.
  • Repeat the same user interactions 10 times to amplify the leak.
  • Use
    take_memory_snapshot
    to save
    .heapsnapshot
    files to disk at baseline, target (after actions), and final (after reverting actions) states.

2. Using Memlab to Find Leaks (Recommended)

Once you have generated

.heapsnapshot
files using
take_memory_snapshot
, use
memlab
to automatically find memory leaks.

  • Read references/memlab.md for how to use
    memlab
    to analyze the generated heapsnapshots.
  • Do not read raw
    .heapsnapshot
    files using
    read_file
    or
    cat
    .

3. Identifying Common Leaks

When you have found a leak trace (e.g., via

memlab
output), you must identify the root cause in the code.

4. Fallback: Comparing Snapshots Manually

If

memlab
is not available, you MUST use the fallback script in the references directory to compare two
.heapsnapshot
files and identify the top growing objects and common leak types.

Run the script using Node.js:

node skills/memory-leak-debugging/references/compare_snapshots.js <baseline.heapsnapshot> <target.heapsnapshot>

The script will analyze and output the top growing objects by size and highlight the 3 most common types of memory leaks (e.g., Detached DOM nodes, closures, Contexts) if they are present.